Abstract : A study is being conducted at the (AF) Aerospace Medical Research Lab. to investigate different types of stick controllers that can be used in a complex G environment. The purpose of this study is to develop impedance models to show the biomechanical effects of stick feedthrough as the human body is subjected to low frequency G stress fields. These impedance models will extend previous work developed in the vibration area to the low frequency vibration fields that commonly occur in modern fighter aircraft (e.g. the AFTI/F-16 with lateral acceleration fields). Another purpose is to investigate how human subjects use displacement and force feedbacks in side arm controllers.